Leases

12 Months Ended

Dec. 31, 2020

The Company currently has operating leases for office and research laboratory space, equipment, and vehicles under agreements expiring at various dates through 2044, which include renewal options on leases which the Company is reasonably certain to exercise.

For the years ended December 31, 2020, and 2019, the operating lease expense was $11.1 million and $10.8 million, respectively. For the years ended December 31, 2020, and 2019, the Company paid $9.6 million and $4.9 million, respectively,

for amounts included in the measurement of operating lease liabilities and recorded $1.7 million and $21.8 million, respectively, of right-of-use assets and $0.5 million and $19.4 million, respectively of tenant improvements paid through lease incentives in exchange for new operating lease liabilities.

Commitments under finance leases are not significant for the years ended December 31, 2020, and 2019.

Supplemental balance sheet information related to operating leases were as follows:


(in thousands, except year and discount rate amounts)	December 31, 2020			December 31, 2019
Operating lease ROU asset	$	23,296		$	33,315

Current portion of the operating lease liabilities	$	6,872		$	7,189
Non-current portion of the operating lease liabilities	45,604			53,531
Total operating lease liability	$	52,476		$	60,720

Weighted-average remaining lease terms (years)	19.8			18.2
Weighted-average discount rate	13.0		%	13.1		%

At December 31, 2020, the future minimum operating lease payments were as follows:


(in thousands)	Operating Lease
2021	$	8,549
2022	8,494
2023	8,691
2024	8,404
2025	8,371
Thereafter	153,241
Total lease payments	195,750
Less lease incentives	(28,939)
Less imputed interest	(114,335)
Total operating lease liability	$	52,476

At December 31, 2019, the future minimum operating lease payments were as follows:


(in thousands)	Operating Lease
2020	$	9,738
2021	10,787
2022	10,459
2023	10,809
2024	10,582
Thereafter	163,266
Total lease payments	$	215,641
Less lease incentives	(28,939)
Less imputed interest	(125,982)
Total operating lease liability	$	60,720

Rent expense, including fees for utilities and common area maintenances under ASC 840 for the year ended December 31, 2018 was $5.7 million.